Two-storey wraparound extensions in Oxfordshire

Oxfordshire at a glance

Nation: England
Price region: South East England
Postcode areas: OX, RG, SN
Towns covered: 13 listed below, plus surrounding villages
Approval route: Planning permission is needed: the side part takes it outside permitted development in England.
Site visits: Free, no obligation

What a two-storey wraparound extension involves

A two-storey wraparound extension is an L-shaped addition that extends both the side and the rear of your house, on two floors. It gives one of the largest gains in floor space of any extension, typically a big open-plan kitchen and living area below and two or more bedrooms or bathrooms above. In England it needs planning permission, because the side part is more than one storey.

Across Oxfordshire we cover Oxford (OX1), Banbury (OX15), Abingdon (OX13), Bicester (OX6), Didcot (OX11) and Witney (OX7), plus the smaller places around them.

Guide price in South East England

Our guide for South East England is £2,360–£3,250 per m² including VAT. On a project with an L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space), that puts a two-storey wraparound extension in Oxfordshire at roughly £132,500–£181,500. Kitchens, bathroom fittings and flooring are priced separately so you can compare like with like.

Spec	Per m²	Typical project
Essential	£2,180–£2,990 per m²	£122,000–£167,000
Standard	£2,360–£3,250 per m²	£132,500–£181,500
Premium	£2,840–£3,890 per m²	£159,000–£218,000

Rules in England

In England, a two-storey wraparound extension needs householder planning permission, because any extension beyond a side wall must be single storey to be permitted development. The application costs £548 (or £575 for applications made from 8 December 2026). Councils weigh the side part against the street scene and the rear part against neighbours' light and outlook, and should decide within 8 weeks of validation.

Approval in England: Householder planning application: £548 (or £575 for applications made from 8 December 2026). Lawful development certificate: £274 (about £288 for applications from 8 December 2026). Councils should decide householder applications within 8 weeks of validation.

Building regulations: Building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end.

The Party Wall etc. Act 1996 applies, so notices may be needed for work on or near a shared wall or boundary.

Getting the design right

Daylight to the middle

A deep L-shaped plan can leave the middle of the ground floor dark, because the old rear rooms are now enclosed. We use wide rear openings, a well-placed stair and, where part of the extension is single storey, roof lights, while keeping total glazing within the Part L allowance.

The corner post

At the outside corner of the L, there is no existing wall to carry the floor above. Opening the ground floor fully usually means a steel frame or a corner post, and the engineer's design sets how slim it can be. We decide early whether you want a clear corner or a visible post.

How we work in Oxfordshire

Understand the brief
At your home in Oxfordshire we agree what you need: bedroom count, bathroom, kitchen space, and how much garden you want to keep.
Choose the approval route
Some designs fit permitted development, most need a householder application. We decide which applies in England before drawing in detail.
Fixed price in writing
With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.
Finish and certify
Second fix, plastering and making good, then building control's final inspection and the completion paperwork.

Towns we cover in Oxfordshire

Two-storey wraparound extensions in Oxfordshire: questions

How much does a two-storey wraparound extension cost in Oxfordshire?

In South East England our guide is £2,360–£3,250 per m² including VAT, so about £132,500–£181,500 for an L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space). Essential and Premium specs move that by roughly 8% down or 20% up.

Can I stay at home during a wraparound extension?

Many people do, but a wraparound affects two sides of the house and usually the kitchen, so there will be weeks without a full kitchen. We plan a temporary kitchen, keep a route through the house and seal off the work area. For some families, moving out while the rear wall is opened up is easier.

Can a wraparound extension be part single, part two-storey?

Yes. Many wraparounds keep the rear part single storey with roof lights over the kitchen and put the two-storey part to the side. This can reduce the effect on neighbours and the cost. We set out both options at the design stage, so you can compare floor space against price before choosing.

Is a wraparound extension better than separate side and rear extensions?

Building both at once usually costs less than two separate projects, because you pay for one set-up, one scaffold, one roof junction and one set of approvals. It also lets the layout be designed as a whole. The trade-off is a larger single outlay and a longer build, often 16 to 24 weeks at this size.

Will I need planning permission in Oxfordshire?

Oxfordshire is in England. Planning permission is needed: the side part takes it outside permitted development in England.

Neighbouring areas

All extension services in Oxfordshire · About two-storey wraparound extensions